The majority of the adverse effects of climate change are experienced by poor and low-income communities around the world, who have much higher levels of vulnerability to environmental determinants of health, wealth and other factors, and much lower levels of capacity available for coping with environmental change. A report on the global human impact of climate change published by the Global Humanitarian Forum in 2009, estimated more than 300,000 deaths and about $125 billion in economic losses each year, and indicating that most climate change induced mortality is due to worsening floods and droughts in developing countries.[8]

Most of the key vulnerabilities to climate change are related to climate phenomena that exceed thresholds for adaptation; such as extreme weather events or abrupt climate change, as well as limited access to resources (financial, technical, human, institutional) to cope. In 2007, the IPCC published a report of key vulnerabilities of industry, settlements, and society to climate change.[9] This assessment included a level of confidence for each key vulnerability:

Very high confidence: Interactions between climate change and urbanization: this is most notable in developing countries, where urbanization is often focused in vulnerable coastal areas.

High confidence:

Interactions between climate change and global economic growth: Stresses due to climate change are not only linked to the impacts of climate change, but also to the impacts of climate change policies. For example, these policies might affect development paths by requiring high cost fuel choices.

Fixed physical infrastructures that are important in meeting human needs: These include infrastructures that are susceptible to damage from extreme weather events or sea level rise, and infrastructures that are already close to being inadequate.

Climate change poses a wide range of risks to population health – risks that will increase in future decades, often to critical levels, if global climate change continues on its current trajectory.[10] The three main categories of health risks include: (i) direct-acting effects (e.g. due to heat waves, amplified air pollution, and physical weather disasters), (ii) impacts mediated via climate-related changes in ecological systems and relationships (e.g. crop yields, mosquito ecology, marine productivity), and (iii) the more diffuse (indirect) consequences relating to impoverishment, displacement, resource conflicts (e.g. water), and post-disaster mental health problems.

Climate change thus threatens to slow, halt or reverse international progress towards reducing child under-nutrition, deaths from diarrheal diseases and the spread of other infectious diseases. Climate change acts predominantly by exacerbating the existing, often enormous, health problems, especially in the poorer parts of the world. Current variations in weather conditions already have many adverse impacts on the health of poor people in developing nations,[11] and these too are likely to be 'multiplied' by the added stresses of climate change.

A changing climate thus affects the prerequisites of population health: clean air and water, sufficient food, natural constraints on infectious disease agents, and the adequacy and security of shelter. A warmer and more variable climate leads to higher levels of some air pollutants. It increases the rates and ranges of transmission of infectious diseases through unclean water and contaminated food, and by affecting vector organisms (such as mosquitoes) and intermediate or reservoir host species that harbour the infectious agent (such as cattle,[12]bats and rodents). Changes in temperature, rainfall and seasonality compromise agricultural production in many regions, including some of the least developed countries, thus jeopardising child health and growth and the overall health and functional capacity of adults. As warming proceeds, the severity (and perhaps frequency) of weather-related disasters will increase – and appears to have done so in a number of regions of the world over the past several decades.[13] Therefore, in summary, global warming, together with resultant changes in food and water supplies, can indirectly cause increases in a range of adverse health outcomes, including malnutrition, diarrhea, injuries, cardiovascular and respiratory diseases, and water-borne and insect-transmitted diseases.

Health equity and climate change have a major impact on human health and quality of life, and are interlinked in a number of ways. The report of the WHO Commission on Social Determinants of Health points out that disadvantaged communities are likely to shoulder a disproportionate share of the burden of climate change because of their increased exposure and vulnerability to health threats. Over 90 percent of malaria and diarrhea deaths are borne by children aged 5 years or younger, mostly in developing countries.[14] Other severely affected population groups include women, the elderly and people living in small island developing states and other coastal regions, mega-cities or mountainous areas.[15]

Indirect - "Threats to emotional well-being based on observation of impacts and concern or uncertainty about future risks"

Psychosocial – "Chronic social and community effects of heat, drought, migrations, and climate-related conﬂicts, and postdisaster adjustment" A psychological impact is shown through peoples behaviours and how they act towards the actual situation. The topic of climate change is very complex and difficult for people to understand, which effects how they act upon it. It is shown by Ranney and Clark(2016)[17] that by informing people to make them understand the topic of climate science clearly, it promotes the change in behaviour towards mitigation of climate change.

This trend towards more variability and fluctuation is perhaps more important, in terms of its impact on human health, than that of a gradual and long-term trend towards higher average temperature.[18] Infectious disease often accompanies extreme weather events, such as floods, earthquakes and drought.[citation needed] These local epidemics occur due to loss of infrastructure, such as hospitals and sanitation services, but also because of changes in local ecology and environment.

Climate change may lead to dramatic increases in prevalence of a variety of infectious diseases. Beginning in the mid-'70s, there has been an “emergence, resurgence and redistribution of infectious diseases”.[18] Reasons for this are likely multicausal, dependent on a variety of social, environmental and climatic factors, however, many argue that the “volatility of infectious disease may be one of the earliest biological expressions of climate instability”.[18] Though many infectious diseases are affected by changes in climate, vector-borne diseases, such as malaria, dengue fever and leishmaniasis, present the strongest causal relationship. Observation and research detect a shift of pests and pathogens in the distribution away from the equator and towards Earth's poles.[19]

Increased precipitation like rain could increase the number of mosquitos indirectly by expanding larval habitat and food supply. Malaria kills approximately 300,000 children (under age 5) annually, poses an imminent threat through temperature increase .[20] Models suggest, conservatively, that risk of malaria will increase 5-15% by 2100 due to climate change.[21] In Africa alone, according to the MARA Project (Mapping Malaria Risk in Africa),[22] there is a projected increase of 16–28% in person-month exposures to malaria by 2100.[23]

Sociodemographic factors include, but are not limited to: patterns of human migration and travel, effectiveness of public health and medical infrastructure in controlling and treating disease, the extent of anti-malarialdrug resistance and the underlying health status of the population at hand.[24] Environmental factors include: changes in land-use (e.g. deforestation), expansion of agricultural and water development projects (which tend to increase mosquito breeding habitat), and the overall trend towards urbanization (i.e. increased concentration of human hosts). Patz and Olson argue that these changes in landscape can alter local weather more than long term climate change.[20] For example, the deforestation and cultivation of natural swamps in the African highlands has created conditions favourable for the survival of mosquito larvae, and has, in part, led to the increasing incidence of malaria.[20] The effects of these non-climatic factors complicate things and make a direct causal relationship between climate change and malaria difficult to confirm. It is highly unlikely that climate exerts an isolated effect.

A sustained wet-bulb temperature exceeding 35° is a threshold at which the resilience of human systems is no longer able to adequately cool the skin. A study by NOAA from 2013 concluded that heat stress will reduce labor capacity considerably under current emissions scenarios.[26] There is evidence to show that high temperatures can increase mortality rates among fetuses and children[27] Although the main focus is often on the health impacts and risks of higher temperatures, it should be remembered that they also reduce learning and worker productivity, which can impact a country's economy and development.

The freshwater resources that humans rely on are highly sensitive to variations in weather and climate. In 2007, the IPCC reported with high confidence that climate change has a net negative impact on water resources and freshwater ecosystems in all regions.[28] The IPCC also found with very high confidence that arid and semi-arid areas are particularly exposed to freshwater impacts.[28]

As the climate warms, it changes the nature of global rainfall, evaporation, snow, stream flow and other factors that affect water supply and quality. Specific impacts include:

Sea level rise is projected to increase salt-water intrusion into groundwater in some regions. This reduces the amount of freshwater available for drinking and farming.[29][30]

In some areas, shrinking glaciers and snow deposits threaten the water supply.[31] Areas that depend on melted water runoff will likely see that runoff depleted, with less flow in the late summer and spring peaks occurring earlier.[29] This can affect the ability to irrigate crops. (This situation is particularly acute for irrigation in South America,[32] for irrigation and drinking supplies in Central Asia, and for hydropower in Norway, the Alps, and the Pacific Northwest of North America.)

Increased extreme weather means more water falls on hardened ground unable to absorb it, leading to flash floods instead of a replenishment of soil moisture or groundwater levels.[33]

Increased evaporation will reduce the effectiveness of reservoirs.

At the same time, human demand for water will grow for the purposes of cooling and hydration.

Climate change causes displacement of people in several ways, the most obvious—and dramatic—being through the increased number and severity of weather-related disasters which destroy homes and habitats causing people to seek shelter or livelihoods elsewhere. Effects of climate change such as desertification and rising sea levels gradually erode livelihood and force communities to abandon traditional homelands for more accommodating environments. This is currently happening in areas of Africa’s Sahel, the semi-arid belt that spans the continent just below its northern deserts. Deteriorating environments triggered by climate change can also lead to increased conflict over resources which in turn can displace people.[34]

The IPCC has estimated that 150 million environmental migrants will exist by the year 2050, due mainly to the effects of coastal flooding, shoreline erosion and agricultural disruption.[35] However, the IPCC also cautions that it is extremely difficult to measure the extent of environmental migration due to the complexity of the issue and a lack of data.[9]

According to the Internal Displacement Monitoring Centre, more than 42 million people were displaced in Asia and the Pacific during 2010 and 2011, more than twice the population of Sri Lanka. This figure includes those displaced by storms, floods, and heat and cold waves. Still others were displaced drought and sea-level rise. Most of those compelled to leave their homes eventually returned when conditions improved, but an undetermined number became migrants, usually within their country, but also across national borders.[36]

Asia and the Pacific is the global area most prone to natural disasters, both in terms of the absolute number of disasters and of populations affected. It is highly exposed to climate impacts, and is home to highly vulnerable population groups, who are disproportionately poor and marginalized. A recent Asian Development Bank report highlights “environmental hot spots” that are particular risk of flooding, cyclones, typhoons, and water stress.[37]

Some Pacific Ocean island nations, such as Tuvalu, Kiribati, and the Maldives,[38] are considering the eventual possibility of evacuation, as flood defense may become economically unrealistic. Tuvalu already has an ad hoc agreement with New Zealand to allow phased relocation.[39] However, for some islanders relocation is not an option. They are not willing to leave their homes, land and families. Some simply don’t know the threat that climate change has on their island and this is mainly down to the lack of awareness that climate change even exists. In Vutia on Viti Levu, Fiji’s main island, half the respondents to a survey had not heard of climate change (Lata and Nuun 2012). Even where there is awareness many believe that it is a problem caused by developed countries and should therefore be solved by developed countries.[40]

Governments have considered various approaches to reduce migration compelled by environmental conditions in at-risk communities, including programs of social protection, livelihoods development, basic urban infrastructure development, and disaster risk management. Some experts even support migration as an appropriate way for people to cope with environmental changes. However, this is controversial because migrants – particularly low-skilled ones – are among the most vulnerable people in society and are often denied basic protections and access to services.[37]

Climate change has the potential to exacerbate existing tensions or create new ones — serving as a threat multiplier. It can be a catalyst for violent conflict and a threat to international security.[48][49] A meta-analysis of over 50 quantitative studies that examine the link between climate and conflict found that "for each 1 standard deviation (1σ) change in climate toward warmer temperatures or more extreme rainfall, median estimates indicate that the frequency of interpersonal violence rises 4% and the frequency of intergroup conflict rises 14%".[50][51] The IPCC has suggested that the disruption of environmental migration may serve to exacerbate conflicts,[52] though they are less confident of the role of increased resource scarcity.[9] Of course, climate change does not always lead to violence, and conflicts are often caused by multiple interconnected factors.[53]

A variety of experts have warned that climate change may lead to increased conflict. The Military Advisory Board, a panel of retired U.S. generals and admirals, predicted that global warming will serve as a "threat multiplier" in already volatile regions.[54] The Center for Strategic and International Studies and the Center for a New American Security, two Washington think tanks, have reported that flooding "has the potential to challenge regional and even national identities," leading to "armed conflict over resources." They indicate that the greatest threat would come from "large-scale migrations of people — both inside nations and across existing national borders."[55] However, other researchers have been more skeptical: One study found no statistically meaningful relationship between climate and conflict using data from Europe between the years 1000 and 2000.[56]

The link between climate change and security is a concern for authorities across the world, including United Nations Security Council and the G77 group of developing nations. Climate change's impact as a security threat is expected to hit developing nations particularly hard. In Britain, Foreign SecretaryMargaret Beckett has argued that "An unstable climate will exacerbate some of the core drivers of conflict, such as migratory pressures and competition for resources."[57]
The links between the human impact of climate change and the threat of violence and armed conflict are particularly important because multiple destabilizing conditions are affected simultaneously.

Experts have suggested links to climate change in several major conflicts:

Additionally, researchers studying ancient climate patterns (paleoclimatology) have shown that long-term fluctuations of war frequency and population changes have followed cycles of temperature change since the preindustrial era.[68] A 2016 study finds that "drought can contribute to sustaining conflict, especially for agriculturally dependent groups and politically excluded groups in very poor countries. These results suggest a reciprocal nature–society interaction in which violent conflict and environmental shock constitute a vicious circle, each phenomenon increasing the group’s vulnerability to the other."[69]

The consequences of climate change and poverty are not distributed uniformly within communities. Individual and social factors such as gender, age, education, ethnicity, geography and language lead to differential vulnerability and capacity to adapt to the effects of climate change. Climate change effects such as hunger, poverty and diseases like diarrhea and malaria, disproportionately impact children; about 90 percent of malaria and diarrhea deaths are among young children. Children are also 14–44 percent more likely to die from environmental factors,[70] again leaving them the most vulnerable.Those in urban areas will be affected by lower air quality and overcrowding, and will struggle the most to better their situation.[14]

As the World Meteorological Organization explains, "recent increase in societal impact from tropical cyclones has largely been caused by rising concentrations of population and infrastructure in coastal regions."[71] Pielke et al. (2008) normalized mainland U.S. hurricane damage from 1900 to 2005 to 2005 values and found no remaining trend of increasing absolute damage. The 1970s and 1980s were notable because of the extremely low amounts of damage compared to other decades. The decade 1996–2005 has the second most damage among the past 11 decades, with only the decade 1926–1935 surpassing its costs. The most damaging single storm is the 1926 Miami hurricane, with $157 billion of normalized damage.[72]

The American Insurance Journal predicted that "catastrophe losses should be expected to double roughly every 10 years because of increases in construction costs, increases in the number of structures and changes in their characteristics."[73] The Association of British Insurers has stated that limiting carbon emissions would avoid 80% of the projected additional annual cost of tropical cyclones by the 2080s. The cost is also increasing partly because of building in exposed areas such as coasts and floodplains. The ABI claims that reduction of the vulnerability to some inevitable effects of climate change, for example through more resilient buildings and improved flood defences, could also result in considerable cost-savings in the longterm.[74]

A major challenge for human settlements is sea level rise, indicated by ongoing observation and research of rapid declines in ice-mass balance from both Greenland and Antarctica. Estimates for 2100 are at least twice as large as previously estimated by IPCC AR4, with an upper limit of about two meters.[75] Depending on regional changes, increased precipitation patterns can cause more flooding or extended drought stresses water resources.

For historical reasons to do with trade, many of the world's largest and most prosperous cities are on the coast. In developing countries, the poorest often live on floodplains, because it is the only available space, or fertile agricultural land. These settlements often lack infrastructure such as dykes and early warning systems. Poorer communities also tend to lack the insurance, savings, or access to credit needed to recover from disasters.

In a journal paper, Nicholls and Tol (2006) considered the effects of sea level rise:[76]

The most vulnerable future worlds to sea-level rise appear to be the A2 and B2 [IPCC] scenarios, which primarily reflects differences in the socio-economic situation (coastal population, Gross Domestic Product (GDP) and GDP/capita), rather than the magnitude of sea-level rise. Small islands and deltaic settings stand out as being more vulnerable as shown in many earlier analyses. Collectively, these results suggest that human societies will have more choice in how they respond to sea-level rise than is often assumed. However, this conclusion needs to be tempered by recognition that we still do not understand these choices and significant impacts remain possible.

The IPCC reported that socioeconomic impacts of climate change in coastal and low-lying areas would be overwhelmingly adverse. The following impacts were projected with very high confidence:[77]

Coastal and low-lying areas would be exposed to increasing risks including coastal erosion due to climate change and sea level rise.

By the 2080s, millions of people would experience floods every year due to sea level rise. The numbers affected were projected to be largest in the densely populated and low-lying mega-deltas of Asia and Africa; and smaller islands were judged to be especially vulnerable.

A study in the April 2007 issue of Environment and Urbanization reports that 634 million people live in coastal areas within 30 feet (9.1 m) of sea level.[78] The study also reported that about two thirds of the world's cities with over five million people are located in these low-lying coastal areas.

Oil and natural gas infrastructure is vulnerable to the effects of climate change and the increased risk[citation needed] of disasters such as storm, cyclones, flooding and long-term increases in sea level. Minimising these risks by building in less disaster prone areas, can be expensive and impossible in countries with coastal locations or island states. All thermal power stations depend on water to cool them. Not only is there increased demand for fresh water, but climate change can increase the likelihood of drought and fresh water shortages. Another impact for thermal power plants, is that increasing the temperatures in which they operate reduces their efficiency and hence their output. The source of oil often comes from areas prone to high natural disaster risks; such as tropical storms, hurricanes, cyclones, and floods. An example is Hurricane Katrina's impact on oil extraction in the Gulf of Mexico, as it destroyed 126 oil and gas platforms and damaged 183 more.[79]

Climate change, along with extreme weather and natural disasters can affect nuclear power plants in a similar way to those using oil, coal, and natural gas. However, the impact of water shortages on nuclear power plants cooled by rivers will be greater than on other thermal power plants. This is because old reactor designs with water-cooled cores must run at lower internal temperatures and thus, paradoxically, must dump more heat to the environment to produce a given amount of electricity. This situation has forced some nuclear reactors to be shut down and will do so again unless the cooling systems of these plants are enhanced to provide more capacity. Nuclear power supply was diminished by low river ﬂow rates and droughts, which meant rivers had reached the maximum temperatures for cooling. Such shutdowns happened in France during the 2003 and 2006 heat waves. During the heat waves, 17 reactors had to limit output or shut down. 77% of French electricity is produced by nuclear power; and in 2009 a similar situation created a 8GW shortage, and forced the French government to import electricity. Other Cases have been reported from Germany, where extreme temperatures have reduced nuclear power production 9 times due to high temperatures between 1979 and 2007. In particular:

Changes in the amount of river flow will correlate with the amount of energy produced by a dam. Lower river flows because of drought, climate change, or upstream dams and diversions, will reduce the amount of live storage in a reservoir; therefore reducing the amount of water that can be used for hydroelectricity. The result of diminished river flow can be a power shortage in areas that depend heavily on hydroelectric power. The risk of flow shortage may increase as a result of climate change. Studies from the Colorado River in the United States suggests that modest climate changes (such as a 2 degree change in Celsius that could result in a 10% decline in precipitation), might reduce river run-off by up to 40%. Brazil in particular, is vulnerable due to its having reliance on hydroelectricity as increasing temperatures, lower water ﬂow, and alterations in the rainfall regime, could reduce total energy production by 7% annually by the end of the century.[79]

The scientific evidence for links between global warming and the increasing cost of natural disasters due to weather events[81] is weak, but, nevertheless, prominent mainstream environmental spokesmen such as Barack Obama and Al Gore have emphasized the possible connection.[82] For the most part increased costs due to events such as Hurricane Sandy[83] are due to increased exposure to loss resulting from building insured facilities in vulnerable locations.[84] This information has been denounced by Paul Krugman[85] and ThinkProgress as climate change denial.[86]

An industry directly affected by the risks of climate change is the insurance industry.[87] According to a 2005 report from the Association of British Insurers, limiting carbon emissions could avoid 80% of the projected additional annual cost of tropical cyclones by the 2080s.[88] A June 2004 report by the Association of British Insurers declared "Climate change is not a remote issue for future generations to deal with; it is, in various forms here already, impacting on insurers' businesses now."[89] The report noted that weather-related risks for households and property were already increasing by 2–4% per year due to the changing weather conditions, and claims for storm and flood damages in the UK had doubled to over £6 billion over the period from 1998–2003 compared to the previous five years. The results are rising insurance premiums, and the risk that in some areas flood insurance will become unaffordable for those in the lower income brackets.

Financial institutions, including the world's two largest insurance companies: Munich Re and Swiss Re, warned in a 2002 study that "the increasing frequency of severe climatic events, coupled with social trends could cost almost 150 billion US$ each year in the next decade".[90] These costs would burden customers, taxpayers, and the insurance industry, with increased costs related to insurance and disaster relief.

In the United States, insurance losses have also greatly increased. It has been shown that a 1% climb in annual precipitation can increase catastrophe loss by as much as 2.8%.[91] Gross increases are mostly attributed to increased population and property values in vulnerable coastal areas; though there was also an increase in frequency of weather-related events like heavy rainfalls since the 1950s.[92]

^America's Climate Choices. Washington, D.C.: The National Academies Press. 2011. p. 15. ISBN978-0-309-14585-5. The average temperature of the Earth’s surface increased by about 1.4 °F (0.8 °C) over the past 100 years, with about 1.0 °F (0.6 °C) of this warming occurring over just the past three decades

^Pielke, Roger (January 29, 2015). The Rightful Place of Science: Disasters and Climate Change. Consortium for Science, Policy & Outcomes, Arizona State University. p. 6. there is precious little evidence to suggest that the blame for the increasing tally of disaster costs can be placed on more frequent or extreme weather events attributable to human-caused climate change.

^Pielke, Roger (January 29, 2015). The Rightful Place of Science: Disasters and Climate Change. Consortium for Science, Policy & Outcomes, Arizona State University. p. 21. Economic growth, including greater concentrations of people and wealth in periled areas and rising insurance penetration, is the most important driver of increasing losses.

^Paul Krugman (March 23, 2014). "Tarnished Silver". The New York Times. Retrieved April 16, 2015. a known irresponsible skeptic

1.
Global warming
–
Global warming and climate change are terms for the observed century-scale rise in the average temperature of the Earths climate system and its related effects. Multiple lines of evidence show that the climate system is warming. The largest human influence has been emission of gases such as carbon dioxide, methane. These findings have been recognized by the science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing. Future climate change and associated impacts will differ from region to region around the globe, anticipated effects include warming global temperature, rising sea levels, changing precipitation, and expansion of deserts in the subtropics. Warming is expected to be greater over land than over the oceans and greatest in the Arctic, with the retreat of glaciers, permafrost. Effects significant to humans include the threat to security from decreasing crop yields. Possible societal responses to global warming include mitigation by emissions reduction, adaptation to its effects, building systems resilient to its effects, most countries are parties to the United Nations Framework Convention on Climate Change, whose ultimate objective is to prevent dangerous anthropogenic climate change. Public reactions to global warming and concern about its effects are also increasing, a global 2015 Pew Research Center report showed a median of 54% consider it a very serious problem. There are significant regional differences, with Americans and Chinese among the least concerned, the global average surface temperature shows a warming of 0.85 °C in the period 1880 to 2012, based on multiple independently produced datasets. Earths average surface temperature rose by 0. 74±0.18 °C over the period 1906–2005, the rate of warming almost doubled for the last half of that period. The rest has melted ice and warmed the continents and atmosphere, the average temperature of the lower troposphere has increased between 0.12 and 0.135 °C per decade since 1979, according to satellite temperature measurements. The warming that is evident in the temperature record is consistent with a wide range of observations. The probability that these changes could have occurred by chance is virtually zero, temperature changes vary over the globe. Since 1979, land temperatures have increased about twice as fast as ocean temperatures, ocean temperatures increase more slowly than land temperatures because of the larger effective heat capacity of the oceans and because the ocean loses more heat by evaporation. Since the beginning of industrialisation the temperature difference between the hemispheres has increased due to melting of sea ice and snow in the North. Average arctic temperatures have been increasing at almost twice the rate of the rest of the world in the past 100 years, the thermal inertia of the oceans and slow responses of other indirect effects mean that climate can take centuries or longer to adjust to changes in forcing. Some of this warming will be driven by past natural forcings which are still seeking equilibrium in the climate system

2.
Effects of global warming
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The effects of global warming are the environmental and social changes caused by human emissions of greenhouse gases. There is a consensus that climate change is occurring. Many impacts of change have already been observed, including glacier retreat, changes in the timing of seasonal events. Future effects of change will vary depending on climate change policies. The two main policies to address climate change are reducing human greenhouse gas emissions and adapting to the impacts of climate change, near-term climate change policies could significantly affect long-term climate change impacts. Stringent mitigation policies might be able to limit warming to around 2 °C or below. Without mitigation, increased demand and extensive use of fossil fuels might lead to global warming of around 4 °C. Higher magnitudes of warming would be more difficult to adapt to. In this article, climate change means a change in climate that persists over a period of time. The World Meteorological Organization defines this time period as 30 years, examples of climate change include increases in global surface temperature, changes in rainfall patterns, and changes in the frequency of extreme weather events. Changes in climate may be due to causes, e. g. changes in the suns output, or due to human activities. Also, the term anthropogenic forcing refers to the influence exerted on a habitat or chemical environment by humans and this article breaks down some of the impacts of climate change according to different levels of future global warming. This way of describing impacts has, for instance, been used in the IPCC Assessment Reports on climate change, the instrumental temperature record shows global warming of around 0.6 °C during the 20th century. The future level of warming is uncertain, but a wide range of estimates have been made. The IPCCs SRES scenarios have been used to make projections of future climate change. The SRES scenarios are baseline scenarios, which means that they do not take into account any current or future measures to limit GHG emissions, emissions projections of the SRES scenarios are broadly comparable in range to the baseline emissions scenarios that have been developed by the scientific community. In the IPCC Fourth Assessment Report, changes in global mean temperature were projected using the six SRES marker emissions scenarios. Emissions projections for the six SRES marker scenarios are representative of the set of forty SRES scenarios

3.
Earth
–
Earth, otherwise known as the World, or the Globe, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets, according to radiometric dating and other sources of evidence, Earth formed about 4.54 billion years ago. Earths gravity interacts with objects in space, especially the Sun. During one orbit around the Sun, Earth rotates about its axis over 365 times, thus, Earths axis of rotation is tilted, producing seasonal variations on the planets surface. The gravitational interaction between the Earth and Moon causes ocean tides, stabilizes the Earths orientation on its axis, Earths lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earths surface is covered with water, mostly by its oceans, the remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earths polar regions are covered in ice, including the Antarctic ice sheet, Earths interior remains active with a solid iron inner core, a liquid outer core that generates the Earths magnetic field, and a convecting mantle that drives plate tectonics. Within the first billion years of Earths history, life appeared in the oceans and began to affect the Earths atmosphere and surface, some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earths distance from the Sun, physical properties, in the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely, over 7.4 billion humans live on Earth and depend on its biosphere and minerals for their survival. Humans have developed diverse societies and cultures, politically, the world has about 200 sovereign states, the modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most often spelled eorðe. It has cognates in every Germanic language, and their proto-Germanic root has been reconstructed as *erþō, originally, earth was written in lowercase, and from early Middle English, its definite sense as the globe was expressed as the earth. By early Modern English, many nouns were capitalized, and the became the Earth. More recently, the name is simply given as Earth. House styles now vary, Oxford spelling recognizes the lowercase form as the most common, another convention capitalizes Earth when appearing as a name but writes it in lowercase when preceded by the. It almost always appears in lowercase in colloquial expressions such as what on earth are you doing, the oldest material found in the Solar System is dated to 4. 5672±0.0006 billion years ago. By 4. 54±0.04 Gya the primordial Earth had formed, the formation and evolution of Solar System bodies occurred along with the Sun

4.
Ecosystem
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An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are regarded as linked together through nutrient cycles, as ecosystems are defined by the network of interactions among organisms, and between organisms and their environment, they can be of any size but usually encompass specific, limited spaces. Energy, water, nitrogen and soil minerals are other essential components of an ecosystem. The energy that flows through ecosystems is obtained primarily from the sun and it generally enters the system through photosynthesis, a process that also captures carbon from the atmosphere. By feeding on plants and on one another, animals play an important role in the movement of matter and they also influence the quantity of plant and microbial biomass present. Ecosystems are controlled both by external and internal factors, other external factors include time and potential biota. Ecosystems are dynamic entities—invariably, they are subject to disturbances and are in the process of recovering from some past disturbance. Ecosystems in similar environments that are located in different parts of the world can have different characteristics simply because they contain different species. The introduction of species can cause substantial shifts in ecosystem function. Internal factors not only control ecosystem processes but are controlled by them and are often subject to feedback loops. Other internal factors include disturbance, succession and the types of species present, although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate. Biodiversity affects ecosystem function, as do the processes of disturbance, classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management, but there is no single, agreed-upon way to do this. The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley, Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment. He later refined the term, describing it as The whole system, including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment. Tansley regarded ecosystems not simply as natural units, but as mental isolates, Tansley later defined the spatial extent of ecosystems using the term ecotope. G. Raymond Lindeman took these ideas one step further to suggest that the flow of energy through a lake was the driver of the ecosystem. Most mineral nutrients, on the hand, are recycled within ecosystems. Ecosystems are controlled both by external and internal factors, external factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem

5.
Effects of global warming on human health
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The effects of global warming include effects on human health. The observed and projected increased frequency and severity of climate related impacts will further exacerbate the effects on human health and this article describes some of those effects on individuals and populations. A good example of the impact of global warming on health can be seen in the disease Erythromelalgia, as climate change proceeds, more Erythromelalgia outbreaks may occur because of the extreme weather events that are projected to increase in coming decades. Warming oceans and a changing climate are resulting in extreme weather patterns which have brought about an increase of infectious diseases—both new and re-emerging. These extreme weather patterns are creating extended rainy seasons in some areas, “The rise of extreme weather is itself a symptom of an unstable climate. Extreme weather also means stronger winds, mosquito-borne diseases are probably the greatest threat to humans as they include malaria, elephantiasis, Rift Valley fever, yellow fever, and dengue fever. Studies are showing higher prevalence of diseases in areas that have experienced extreme flooding. Flooding creates more standing water for mosquitoes to breed, as well, shown that these vectors are able to feed more and grow faster in warmer climates. As the climate warms over the oceans and coastal regions, warmer temperatures are also creeping up to higher elevations allowing mosquitoes to survive in areas they had never been able to before. As the climate continues to warm there is a risk that malaria will make a return to the developed world, ticks are also thriving in the warmer temperatures allowing them to feed and grow at a faster rate. The black legged tick, a carrier of Lyme disease, when not feeding, ticks die when the climate either becomes too cold or when the climate becomes too dry, causing the ticks to dry out. Other diseases on the due to extreme weather include hantavirus, schistosomiasis, onchocerciasis. It also causes the rise in hay fever, as when the weather gets warmer there is a rise in levels in the air. Because of the temperature, parts of the globe could become uninhabitable. The warming oceans are becoming a ground for toxic algae blooms. As the nitrogen and phosphorus levels in the increase, the cholera bacteria that lives within zooplankton emerge from their dormant state. The changing winds and changing ocean currents push the zooplankton toward the coastline, carrying the cholera bacteria, as flooding increases there is also an increase in cholera epidemics as the flood waters that are carrying the bacteria are infiltrating the drinking water supply. El Nino has also linked with cholera outbreaks because this weather pattern warms the shoreline waters

6.
Global warming controversy
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No scientific body of national or international standing disagrees with this view, though a few organizations with members in extractive industries hold non-committal positions. Global warming remains an issue of political debate, often split along party political lines. The sources of funding for those involved with climate science—both supporting and opposing mainstream scientific positions—have been questioned by both sides, There are debates about the best policy responses to the science, their cost-effectiveness and their urgency. Legal cases regarding global warming, its effects, and measures to reduce it have reached American courts, the fossil fuels lobby has been identified as overtly or covertly supporting efforts to undermine or discredit the scientific consensus on global warming. The British press also changed its coverage at the end of 1988, at the same time environmental organizations and the political opposition were demanding solutions that contrasted with the governments. In May 2013 Charles, Prince of Wales took a strong stance criticising both climate change deniers and corporate lobbyists by likening the Earth to a dying patient, a scientific hypothesis is tested to absolute destruction, but medicine cant wait. If a doctor sees a child with a fever, he cant wait for tests and he has to act on what is there. Many European countries took action to reduce gas emissions before 1990. West Germany started to take action after the Green Party took seats in Parliament in the 1980s, all countries of the European Union ratified the 1997 Kyoto Protocol. Substantial activity by NGOs took place as well and it took many years for this particular issue to attract any type of attention. In Europe, the notion of human influence on climate gained wide acceptance more rapidly than in the United States, 87% of Europeans considered climate change to be a very serious or serious problem, while ten per cent did not consider it a serious problem. In 2007, the BBC announced the cancellation of a television special Planet Relief. The editor of BBCs Newsnight current affairs show said, It is absolutely not the BBCs job to save the planet, I think there are a lot of people who think that, but it must be stopped. The fact that half of the American population believe that global warming is caused by human activity could be seen as a victory for these deniers. A compendium of poll results on public perceptions about global warming is below, however, the public is out of step with the scientific community, with 41% believing that climate change is being caused by both human activity and natural processes. 46% believe human activity is the main cause, only a small minority reject anthropogenic climate change, while almost half are very concerned. However, there remains a large proportion who are not fully persuaded, There is still a strong appetite among the public for more information, and 63% say they need this to come to a firm view on the issue and what it means for them. The public continue to externalize climate change to other people, places and times, however, the issue features less prominently nationally and locally, indeed only 9% believe climate change will have a significant impact upon them personally

7.
Drinking water
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Drinking water, also known as potable water or improved drinking water, is water that is safe to drink or to use for food preparation, without risk of health problems. Globally, in 2015, 91% of people had access to suitable for drinking. Nearly 4.2 billion had access to tap water while another 2.4 billion had access to wells or public taps,1.8 billion people still use an unsafe drinking water source which may be contaminated by feces. This can result in infectious diarrhea such as cholera and typhoid among others, the amount of drinking water required is variable. It depends on activity, age, health issues. It is estimated that the average American drinks about one litre of water a day with 95% drinking less than three litres per day, for those working in a hot climate, up to 16 liters a day may be required. Water makes up about 60% of weight in men and 55% of weight in women, infants are about 70% to 80% water while the elderly are around 45%. Typically in developed countries, tap water meets drinking water quality standards, other typical uses include washing, toilets, and irrigation. Greywater may also be used for toilets or irrigation and its use for irrigation however may be associated with risks. Water may also be due to levels of toxins or suspended solids. Reduction of waterborne diseases and development of water resources is a major public health goal in developing countries. Bottled water is sold for consumption in most parts of the world. The word potable came into English from the Late Latin potabilis, the amount of drinking water required is variable. It depends on activity, age, health, and environmental conditions. It is estimated that the average American drinks about one litre of water a day with 95% drinking less than three litres per day, for those working in a hot climate, up to 16 litres per day may be required. Some health authorities have suggested that at least eight glasses of eight fl oz each are required by an adult per day, the British Dietetic Association recommends 1.8 litres. However, various reviews of the evidence performed in 2002 and 2008 could not find any scientific evidence recommending eight glasses of water per day. An individuals thirst provides a guide for how much water they require rather than a specific

8.
Siberia
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Siberia is an extensive geographical region, and by the broadest definition is also known as North Asia. Siberia has historically been a part of Russia since the 17th century, the territory of Siberia extends eastwards from the Ural Mountains to the watershed between the Pacific and Arctic drainage basins. It stretches southwards from the Arctic Ocean to the hills of north-central Kazakhstan and to the borders of Mongolia. With an area of 13.1 million square kilometres, Siberia accounts for 77% of Russias land area and this is equivalent to an average population density of about 3 inhabitants per square kilometre, making Siberia one of the most sparsely populated regions on Earth. If it were a country by itself, it would still be the largest country in area, the origin of the name is unknown. Some sources say that Siberia originates from the Siberian Tatar word for sleeping land, another account sees the name as the ancient tribal ethnonym of the Sirtya, a folk, which spoke a language that later evolved into the Ugric languages. This ethnic group was assimilated to the Siberian Tatar people. The modern usage of the name was recorded in the Russian language after the Empires conquest of the Siberian Khanate, a further variant claims that the region was named after the Xibe people. The Polish historian Chycliczkowski has proposed that the name derives from the word for north. He said that the neighbouring Chinese, Arabs and Mongolians would not have known Russian and he suggests that the name is a combination of two words, su and bir. The region is of significance, as it contains bodies of prehistoric animals from the Pleistocene Epoch. Specimens of Goldfuss cave lion cubs, Yuka and another woolly mammoth from Oymyakon, a rhinoceros from the Kolyma River. The Siberian Traps were formed by one of the largest known volcanic events of the last 500 million years of Earths geological history. They continued for a million years and are considered a cause of the Great Dying about 250 million years ago. At least three species of human lived in Southern Siberia around 40,000 years ago, H. sapiens, H. neanderthalensis, the last was determined in 2010, by DNA evidence, to be a new species. Siberia was inhabited by different groups of such as the Enets, the Nenets, the Huns, the Scythians. The Khan of Sibir in the vicinity of modern Tobolsk was known as a prominent figure who endorsed Kubrat as Khagan of Old Great Bulgaria in 630, the Mongols conquered a large part of this area early in the 13th century. With the breakup of the Golden Horde, the autonomous Khanate of Sibir was established in the late 15th century, turkic-speaking Yakut migrated north from the Lake Baikal region under pressure from the Mongol tribes during the 13th to 15th century

9.
Air pollution
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Air pollution occurs when harmful substances including particulates and biological molecules are introduced into Earths atmosphere. It may cause diseases, allergies or death in humans, it may cause harm to other living organisms such as animals and food crops. Human activity and natural processes can both generate air pollution, indoor air pollution and poor urban air quality are listed as two of the worlds worst toxic pollution problems in the 2008 Blacksmith Institute Worlds Worst Polluted Places report. According to the 2014 WHO report, air pollution in 2012 caused the deaths of around 7 million people worldwide, an air pollutant is a substance in the air that can have adverse effects on humans and the ecosystem. The substance can be particles, liquid droplets, or gases. A pollutant can be of natural origin or man-made, pollutants are classified as primary or secondary. Primary pollutants are usually produced from a process, such as ash from a volcanic eruption, other examples include carbon monoxide gas from motor vehicle exhaust, or the sulfur dioxide released from factories. Secondary pollutants are not emitted directly, rather, they form in the air when primary pollutants react or interact. Ground level ozone is a prominent example of a secondary pollutant, some pollutants may be both primary and secondary, they are both emitted directly and formed from other primary pollutants. Substances emitted into the atmosphere by human activity include, Carbon dioxide - Debate continues over whether carbon dioxide should be classified as an atmospheric pollutant, because of its role as a greenhouse gas it has been described as the leading pollutant and the worst climate pollution. Against this it is argued that carbon dioxide is a component of the atmosphere, essential for plant life. This question of terminology has practical effects, for example as determining whether the U. S. Clean Air Act is deemed to regulate CO2 emissions, CO2 increase in earths atmosphere has been accelerating. Sulfur oxides - particularly sulfur dioxide, a compound with the formula SO2. SO2 is produced by volcanoes and in industrial processes. Coal and petroleum often contain sulfur compounds, and their combustion generates sulfur dioxide, further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2SO4, and thus acid rain. This is one of the causes for concern over the impact of the use of these fuels as power sources. Nitrogen oxides - Nitrogen oxides, particularly nitrogen dioxide, are expelled from high temperature combustion and they can be seen as a brown haze dome above or a plume downwind of cities. Nitrogen dioxide is a compound with the formula NO2

10.
Mosquito
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Mosquitoes are small, midge-like flies that constitute the family Culicidae. Females of most species are ectoparasites, whose tube-like mouthparts pierce the skin to consume blood. The word mosquito is Spanish for little fly, thousands of species feed on the blood of various kinds of hosts, mainly vertebrates, including mammals, birds, reptiles, amphibians, and even some kinds of fish. Some mosquitoes also attack invertebrates, mainly other arthropods, though the loss of blood is seldom of any importance to the victim, the saliva of the mosquito often causes an irritating rash that is a serious nuisance. Much more serious though, are the roles of species of mosquitoes as vectors of diseases. The oldest known mosquito with a similar to modern species was found in 79-million-year-old Canadian amber from the Cretaceous. An older sister species with more primitive features was found in Burmese amber that is 90 to 100 million years old, two mosquito fossils have been found that show very little morphological change in modern mosquitoes against their counterpart from 46 million years ago. These fossils are also the oldest ever found to have blood preserved within their abdomens, the Old and New World Anopheles species are believed to have subsequently diverged about 95 million years ago. The mosquito Anopheles gambiae is currently undergoing speciation into the M and S molecular forms, consequently, some pesticides that work on the M form no longer work on the S form. Over 3,500 species of the Culicidae have already been described and they are generally divided into two subfamilies which in turn comprise some 43 genera. These figures are subject to change, as more species are discovered. The two main subfamilies are the Anophelinae and Culicinae, with their genera as shown in the subsection below, the distinction is of great practical importance because the two subfamilies tend to differ in their significance as vectors of different classes of diseases. Roughly speaking, arboviral diseases such as fever and dengue fever tend to be transmitted by Culicine species. Some transmit various species of malaria, but it is not clear that they ever transmit any form of human malaria. Some species do however transmit various forms of filariasis, much as many Simuliidae do, Anopheline mosquitoes, again not necessarily in the genus Anopheles, sometimes bear pathogenic arboviruses, but it is not yet clear that they ever transmit them as effective vectors. However, all the most important vectors of malaria are Anopheline. Anophelinae Culicinae Mosquitoes are members of a family of nematocerid flies, superficially, mosquitoes resemble crane flies and chironomid flies. In particular, the females of species of mosquitoes are blood-eating pests and dangerous vectors of diseases

Global warming, also referred to as climate change, is the observed century-scale rise in the average temperature of …

Ship tracks can be seen as lines in these clouds over the Atlantic Ocean on the east coast of the United States. Atmospheric particles from these and other sources could have a large effect on climate through the aerosol indirect effect.

The effects of global warming are the environmental and social changes caused (directly or indirectly) by human …

A map that shows ice concentration on 16 September 2012, along with the extent of the previous record low (yellow line) and the mid-September median extent (black line) setting a new record low that was 18 percent smaller than the previous record and nearly 50 percent smaller than the long-term (1979–2000) average.

Precipitation during the 20th century and up through 2008 during global warming, the NOAA estimating an observed trend over that period of 1.87% global precipitation increase per century.

Image: Temperatures across the world in the 1880s (left) and the 1980s (right), as compared to average temperatures from 1951 to 1980 (US EPA)

Image: Map of projected global warming across the globe by the 2050s. Projections based on three SRES greenhouse gas emissions scenarios. Data from CMIP3 (2007)

The global warming controversy concerns the public debate over whether global warming is occurring, how much has …

Antarctic Skin (the roughly top millimeter of land, sea, snow, or ice) temperature trends between 1981 and 2007, based on thermal infrared observations made by a series of NOAA satellite sensors; note that they do not necessarily reflect air temperature trends.

The primitive nature of medieval medicine rendered Europe helpless to the onslaught of the Black Death in the 14th century. Fragment of a miniature from "The Chronicles of Gilles Li Muisis" (1272-1352). Bibliothèque royale de Belgique, MS 13076-77, f. 24v.